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1.
Placenta ; 36(4): 345-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25659497

RESUMO

INTRODUCTION: Pre-eclampsia is a pregnancy-specific disorder and characterized by reduced trophoblast invasion and reduced spiral artery remodeling in the first trimester placenta. A polymorphism located in the promoter region of ACVR2A (rs1424954 (A > G)) has previously been shown to be significantly associated with pre-eclampsia. METHODS: The effects of this variant on ACVR2A expression and its function in the Activin-A signaling pathway were studied by transfections in SGHPL-5 extravillous trophoblasts followed by qRT-PCR. RESULTS: Here we show that the ACVR2A promoter susceptibility variant causes a downregulation of ACVR2A expression. We also provide evidence for transcription of a so-called PROMPT (PROMoter-uPstream-Transcript) in the opposite direction of ACVR2A, containing the polymorphism, and downregulated when the susceptibility allele is carried, which either shares the same promoter as ACVR2A or is a non-coding RNA that is able to enhance ACVR2A transcription. Furthermore, when the effect of the susceptibility variant is mimicked by knockdown of ACVR2A, physiologic concentrations of Activin-A cause a reduction in NODAL mRNA expression in the SGHPL-5 trophoblasts, indicative of a protective effect as reduction in NODAL expression is associated with an increase in trophoblast invasion. However, at pathologic levels of Activin-A, as found in pre-eclampsia, this effect is no longer seen, and we show this is potentially caused by a lack of downregulation of ACVR2B. DISCUSSION: The combined data suggest a double hit phenomenon in which the first hit, the promoter variant, together with the second hit, pathological levels of Activin-A, lead to high levels of NODAL, associated with reduced trophoblast invasion and observed in pre-eclamptic placentas.


Assuntos
Receptores de Activinas Tipo II/genética , Ativinas/metabolismo , Regulação para Baixo , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Transdução de Sinais , Trofoblastos/metabolismo , Receptores de Activinas Tipo II/antagonistas & inibidores , Receptores de Activinas Tipo II/química , Receptores de Activinas Tipo II/metabolismo , Alelos , Linhagem Celular , Éxons , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Proteína Nodal/antagonistas & inibidores , Proteína Nodal/genética , Proteína Nodal/metabolismo , Fragmentos de Peptídeos/agonistas , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/metabolismo , Gravidez , Interferência de RNA , RNA Interferente Pequeno , Proteínas Recombinantes/metabolismo
2.
Mult Scler ; 17(8): 922-30, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21543551

RESUMO

BACKGROUND: The interleukin 7 receptor (IL7R) has been recognized as a susceptibility gene for Multiple Sclerosis (MS). Analysis of rs6897932 (the most strongly MS-associated single nucleotide polymorphism (SNP)), showed effects of genotype on the relative expression of membrane-bound to total amount of IL7R mRNA. OBJECTIVE: We assessed the relevance of IL7R on MS phenotype (including clinical and magnetic resonance imaging (MRI) parameters) at DNA and mRNA level in Dutch patients with MS. METHODS: The genotype of rs6897932 was analyzed in 697 patients with MS and 174 healthy controls. The relevance of genotype and carriership of the C allele on MS phenotype (disease activity and severity, using clinical and MRI parameters) was assessed. In addition, relative gene expression of membrane-bound to total IL7R mRNA was analyzed with respect to disease phenotype in a subgroup of 95 patients with early relapsing MS. RESULTS: In particular, homozygosity for the risk allele is a risk factor for MS in our population (OR(CC vs CT and TT) = 1.65 (95% CI: 1.18-2.30), two-sided p = 0.004). However, no effect of genotype or the relative expression of membrane-bound IL7R (presence of exon 6-7) to total amount of IL7R mRNA (presence of exon 4-5) was found on MS phenotype. DISCUSSION: Homozygosity for the IL7R exon 6 rs6897932 C allele is associated with a higher risk for MS in our Dutch population. No effect was found of genotype or mRNA expression on disease phenotype.


Assuntos
Predisposição Genética para Doença , Esclerose Múltipla/genética , RNA Mensageiro/análise , Receptores de Interleucina-7/genética , Alelos , Genótipo , Humanos , Países Baixos , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único
3.
Neurology ; 75(14): 1228-33, 2010 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-20921509

RESUMO

OBJECTIVE: To determine if myxovirus resistance protein A (MxA) mRNA is related to clinical disease activity in multiple sclerosis (MS). METHODS: Baseline MxA mRNA levels were measured in a prospective cohort of 116 untreated patients with early MS and were related to clinical relapses and MRI at baseline and at follow-up. RESULTS: Low levels of MxA mRNA were associated with the occurrence of relapses (p = 0.002) and contrast-enhancing lesions (CELs) on baseline MRI (p = 0.045). In addition, high baseline MxA mRNA levels were related to a longer time to a first new relapse (hazard ratio [HR] 0.59; 95% confidence interval [CI] 0.35-1.00; p = 0.044). Adding the absence of CELs to high MxA mRNA, the predictive value increased (HR 0.35; 95% CI 0.17-0.74; p = 0.006), clearly showing a cumulative value for combining both factors. CONCLUSIONS: MxA mRNA is related to clinical exacerbations, the number of CELs on MRI, and is indicative for the time to a subsequent relapse. If confirmed, MxA mRNA has potential as a biomarker for clinical disease activity in MS.


Assuntos
Proteínas de Ligação ao GTP/genética , Esclerose Múltipla Recidivante-Remitente/sangue , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Esclerose Múltipla Recidivante-Remitente/genética , RNA Mensageiro/metabolismo , Adulto , Anticorpos Neutralizantes/uso terapêutico , Estudos de Coortes , Avaliação da Deficiência , Feminino , Proteínas de Ligação ao GTP/sangue , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interferon beta/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/terapia , Proteínas de Resistência a Myxovirus , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Curva ROC , Análise de Regressão , Adulto Jovem
4.
Eur J Neurol ; 16(9): 1049-52, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19486142

RESUMO

BACKGROUND: Treatment failure to Interferon-beta (IFNbeta) in multiple sclerosis (MS) can only partly be explained by anti-IFNbeta neutralising antibodies (NAb). Myxovirus resistance protein A (MxA) mRNA, reflecting IFNbeta bioactivity, is studied as an alternative biomarker for IFNbeta therapy response. Although absent IFNbeta bioactivity is associated with NAb and NAb are associated with reduced drug efficacy, the direct relationship between IFNbeta bioactivity and clinical disease activity is largely unknown. METHODS: We enrolled 126 consecutive relapsing-remitting MS patients on IFNbeta treatment. MxA mRNA expression was assessed 4 h after IFNbeta injection. Biological response status was determined after 3 months, by combined measurement of MxA mRNA expression and induction (MxA mRNA expression after/before IFNbeta injection). Patients were considered biological non-responders when both MxA mRNA expression and MxA mRNA induction were negative. RESULTS: Biological non-responders showed a significantly higher annualised relapse rate and smaller proportion relapse-free patients compared with biological responders (relapse rate 0.81 vs. 0.37; proportion relapse free 37% vs. 67%). CONCLUSIONS: Our results suggest that a lack of IFNbeta bioactivity is associated with the occurrence of relapses and therefore can be useful as a biomarker for unresponsiveness to IFNbeta.


Assuntos
Proteínas de Ligação ao GTP/sangue , Interferon beta/sangue , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Adulto , Biomarcadores/sangue , Feminino , Humanos , Interferon beta/uso terapêutico , Masculino , Esclerose Múltipla Recidivante-Remitente/sangue , Proteínas de Resistência a Myxovirus , RNA Mensageiro , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Falha de Tratamento
5.
Mult Scler ; 15(2): 212-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18805837

RESUMO

BACKGROUND: Neutralising antibodies (NAb) to interferon beta (IFN beta) are associated with a reduced bioactivity and efficacy of IFN beta in multiple sclerosis (MS). Unclear is how to apply IFN beta bioactivity measurements (quantification of Myxovirus resistance protein A (MxA) mRNA) in clinical practice. OBJECTIVES: To evaluate value and feasibility of IFN beta bioactivity measurement with a single MxA mRNA measurement for screening and a second measurement before and after IFN beta administration for definite confirmation of IFN beta bioactivity status. METHODS: In 79 MS patients MxA mRNA expression was determined 4 hours after IFN beta administration. If inadequate, MxA mRNA expression testing was repeated 3 months afterwards, comparing post- and pre injection samples to determine whether IFNb bioactivity was persistently lacking. MxA mRNA expression was compared to NA beta titres, determined by the cytopathic effect assay (CPE). RESULTS: NAb titres correlated significantly with MxA mRNA expression and MxA mRNA induction. Of all screened patients, only one patient had adequate MxA mRNA expression and high NAb titres simultaneously. Of the biological non-responders at second measurement (21/55), 17 (81%) were high-titre NAb positive, 1 (5%) was low-titre NAb positive and 3 (14%) were NAb negative. Without considering the pre-injection measurement, two more NAb negative patients would have tested negative for IFN beta bioactivity, emphasizing the need of a pre-injection sample. CONCLUSIONS: Our data suggest that for IFN beta bioactivity screening a single post-injection measurement seems reasonable. However, MxA induction measurement based on both pre- and post-IFN beta injection samples at second measurement is somewhat more precise in determining ultimate IFN beta bioactivity status.


Assuntos
Monitoramento de Medicamentos/métodos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/imunologia , Interferon beta/administração & dosagem , Interferon beta/imunologia , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Adulto , Anticorpos/imunologia , Anticorpos/farmacologia , Estudos de Viabilidade , Feminino , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/imunologia , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Regulação Viral da Expressão Gênica/imunologia , Humanos , Imunoensaio/métodos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/imunologia , Proteínas de Resistência a Myxovirus , Testes de Neutralização , RNA Mensageiro/metabolismo , Adulto Jovem
6.
Placenta ; 29 Suppl A: S78-82, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17959244

RESUMO

Pre-eclampsia and related syndromes, such as the HELLP (haemolysis, elevated liver enzymes and low platelets) syndrome, have a strong genetic component, although the nature, origin and recurrence rate of the genetic risks involved are not necessarily the same for each form of pregnancy-induced hypertension or population. This review addresses these items in the context of the recent understanding that (a) common diseases can be caused by common genetic variations, (b) the placental genotype can control the maternal phenotype, (c) epistasis and epigenetics are involved, and (d) a conserved pathway shared between organs is possible as well as a common, pathophysiological pathway is shared between syndromes.


Assuntos
Regulação da Expressão Gênica/fisiologia , Placenta/fisiologia , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/fisiopatologia , Epigênese Genética/fisiologia , Epistasia Genética , Feminino , Síndrome HELLP/genética , Síndrome HELLP/fisiopatologia , Humanos , Linhagem , Gravidez
7.
Int J Biol Markers ; 22(2): 114-23, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17549667

RESUMO

Microarray-based expression profiling studies of lung adenocarcinomas have defined neuroendocrine subclasses with poor prognosis. As neuroendocrine development is regulated by members of the achaete-scute and atonal classes of basic helix-loop-helix (bHLH) transcription factors, we analyzed lung tumors for expression of these factors. Out of 13 bHLH genes tested, 4 genes, i.e., achaete-scute complex-like 1 (ASCL1, HASH1, Mash1), atonal homolog 1 (ATOH1, HATH1, MATH1), NEUROD4 (ATH-3, Atoh3, MATH-3) and neurogenic differentiation factor 1 (NEUROD1, NEUROD, BETA2), showed differential expression among lung tumors and absent or low expression in normal lung. As expected, tumors that have high levels of ASCL1 also express neuroendocrine markers, and we found that this is accompanied by increased levels of NEUROD1. In addition, we found ATOH1 expression in 9 (16%) out of 56 analyzed adenocarcinomas and these tumors showed neuroendocrine features as shown by dopa decarboxylase mRNA expression and immunostaining for neuroendocrine markers. ATOH1 expression as well as NEUROD4 was observed in small cell lung carcinoma (SCLC), a known neuroendocrine tumor. Since ATOH1 is not known to be involved in normal lung development, our results suggest that aberrant activation of ATOH1 leads to a neuroendocrine phenotype similar to what is observed for ASCL1 activation during normal neuroendocrine development and in lung malignancies. Our preliminary data indicate that patients with ATOH1-expressing adenocarcinomas might have a worse prognosis.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carcinoma Neuroendócrino/genética , Perfilação da Expressão Gênica , Neoplasias Pulmonares/genética , Carcinoma Neuroendócrino/mortalidade , Primers do DNA , Regulação Neoplásica da Expressão Gênica , Humanos , Pulmão/patologia , Proteínas do Tecido Nervoso/genética , Prognóstico , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sobrevida
8.
Prenat Diagn ; 27(2): 146-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17186567

RESUMO

OBJECTIVES: The presence and detectability of placental mRNA in maternal plasma opens possibilities for the development of non-invasive prenatal diagnostic tests. In this study, we tested C21orf105, a chromosome 21-encoded, placentally expressed gene, in maternal plasma of women carrying a fetus with or without trisomy 21. METHODS: Using real-time RT-PCR, we determined transcript levels of target (C21orf105) and reference (hPL) genes in first-trimester plasma samples. Plasma was obtained from first-trimester EDTA blood after two sequential centrifugation steps and stored at -70 degrees C. After RNA extraction, quantitative RT-PCR was performed using Taqman probes. RESULTS: From the 51 samples, 43 samples were conclusive. Comparison of transcript levels of C21orf105 in both groups showed no significant differences. When expressed as ratios of hPL/C21orf105, the differences between trisomy 21 and normal pregnancies remained non-significant. CONCLUSIONS: The amount of C21orf105 mRNA in maternal plasma, although situated in the Down syndrome critical region on chromosome 21 and up regulated in trisomy 21 placentas, is not higher in women carrying a fetus with trisomy 21.


Assuntos
Cromossomos Humanos Par 21/genética , Síndrome de Down/genética , Marcadores Genéticos , Fases de Leitura Aberta/genética , Gravidez/sangue , Diagnóstico Pré-Natal/métodos , RNA Mensageiro/sangue , Adulto , Síndrome de Down/sangue , Feminino , Humanos , Placenta/metabolismo , Lactogênio Placentário/sangue , Lactogênio Placentário/genética , Valor Preditivo dos Testes , Primeiro Trimestre da Gravidez , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
J Reprod Immunol ; 59(1): 29-37, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12892901

RESUMO

C-reactive protein (CRP) is a marker of tissue damage and inflammation. Maternal levels of CRP are elevated in overt preeclampsia, but there is still debate about its use as a predictive marker for preeclampsia during the first and second trimesters of pregnancy. In this study, we measured CRP levels during the first trimester of pregnancy in women who later developed preeclampsia or gave birth to a growth-restricted baby. In total, 107 women from a low-risk population participated in the study, six women developed preeclampsia and nine gave birth to a growth-restricted baby. Although there is a large overlap in measured CRP levels between the three groups, mean CRP levels were significantly elevated in women who later developed preeclampsia (P=0.031) or delivered a growth-restricted baby (P=0.041) when compared with women from the control group, matched for maternal and gestational age, parity, and gravidity. This study shows that in a low-risk population, CRP levels are already elevated between weeks 10 and 14 in pregnant women who develop preeclampsia or deliver a growth-restricted baby.


Assuntos
Proteína C-Reativa/metabolismo , Retardo do Crescimento Fetal/complicações , Pré-Eclâmpsia/sangue , Complicações Cardiovasculares na Gravidez/sangue , Primeiro Trimestre da Gravidez/sangue , Peso ao Nascer , Pressão Sanguínea , Estudos de Casos e Controles , Feminino , Retardo do Crescimento Fetal/sangue , Retardo do Crescimento Fetal/fisiopatologia , Humanos , Recém-Nascido , Tamanho do Órgão , Placenta/irrigação sanguínea , Placenta/patologia , Placenta/fisiopatologia , Pré-Eclâmpsia/complicações , Pré-Eclâmpsia/fisiopatologia , Gravidez , Complicações Cardiovasculares na Gravidez/fisiopatologia
10.
Hum Genet ; 110(3): 279-83, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11935341

RESUMO

Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is an inherited neurologic disorder with macrocephaly before the age of one and slowly progressive deterioration of motor functions. Magnetic resonance imaging shows diffusely abnormal and swollen white matter of the cerebral hemispheres and the presence of subcortical cysts in the anterior-temporal region and often also in the frontoparietal region. Mutations in the MLC1 gene, encoding a putative membrane protein, have been recently identified as a cause for MLC. Here, we describe 14 new mutations in 18 patients. Two identified polymorphisms lead to alterations of amino acid residues. The role, suggested by others, of a mutation in the MLC1gene in catatonic schizophrenia and the possible function of the MLC1 protein as a cation channel are discussed.


Assuntos
Demência Vascular/genética , Transtornos Heredodegenerativos do Sistema Nervoso/genética , Proteínas de Membrana/genética , Mutação , Sequência de Aminoácidos , Animais , Sequência de Bases , Cistos do Sistema Nervoso Central/genética , Cistos do Sistema Nervoso Central/patologia , DNA/genética , Análise Mutacional de DNA , Demência Vascular/patologia , Éxons , Transtornos Heredodegenerativos do Sistema Nervoso/patologia , Humanos , Camundongos , Dados de Sequência Molecular , Canais de Potássio/genética , Esquizofrenia Catatônica/genética , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
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